An operating machine such as a power shovel includes an operating portion such as a bucket. Various drilling tools are attached to the operating portion. For example, a plurality of adaptors is, at predetermined intervals, fixed to a tip end portion of the bucket of the power shovel for drilling. Moreover, teeth as the drilling tools are each attached to the adaptors. The teeth are abraded or damaged in a drilling process, and therefore, are replaced as necessary.
Patent Literature 1 discloses such an attachment pin assembly for attaching the tooth to the adaptor of the bucket.
That is, a pair of first through-holes is formed at the tooth, and a second through-hole is formed at the adaptor. In an attachment state in which the adaptor is inserted into the tooth in contact with the tooth, the first and second through-holes are arranged to penetrate the tooth and the adaptor. In the tooth attachment state in which the adaptor contacts the inside of the tooth, the first and second through-holes are in such a concentric state that the centers thereof are coincident with each other.
The attachment pin assembly includes a circular columnar pin body inserted into the first and second through-holes, a cylindrical bush arranged at an end portion of the pin body in each first through-hole, and a bolt and a washer provided at each end of the pin body to prevent detachment of the bush from the each end of the pin body. Moreover, the bush is movable in an axial direction of the pin body between the adaptor and the washer on an outer peripheral surface of the pin body.